# eHow

How To Calculate The Number of Atoms In Specific Amount of Element: Problem: An element “X” having FCC structure has unit cell edge 500pm. Find the density of X and the number of unit cells for 20g of X. (atomic mass of X = 200g/mol) Solution: Follow the steps: 1-Calculate the volume of length of unit […]

How To Calculate The Radius Of An Ion Problem: A solid compound AB has NaCl structure. If the radius of the cation is 150nm, calculate the radius of anion B. Solution: Follow the steps: 1- Find out the structural arrangement of atoms in the solid compound 2- Find the radius ratio based on the structural […]

How To Calculate The Radius Of A Solid Crystal Element Problem: Iron which crystallizes as body centered cubic lattice has a density of 7.87 g/cm3 at 20˚C. Calculate the radius of iron atom. Solution: Follow the steps: 1- Calculate the length of the unit cell by applying the density formula 2- Find the relation between length […]

Calculating The % Of Empty Space Of A Solid Atom Question: The density of solid copper is 8.83 g/cm3 at 100.0°C. Assume that the copper atom is a sphere of radius 1.02×10-8 cm. Calculate the percentage of empty space of solid copper. (Atomic mass = 63.55) Solution: Follow the steps: 1- Calculate the volume of […]

How To Calculate Van’t Hoff Factor (i) Van’t Hoff Factor (i): It is a measure of degree of dissociation/association of a compound. i = [1 + (y-1)x] y is the number of dissociated ions, x is % value. If i >1, there is dissociation of solute. If i <1, there is association of solute If […]

Calculating The Edge Length of The Unit Cell density = Z x M / x Where Z – is the number of atoms per unit cell, Value for z: z = 1 for simple cubic cell (scc) z = 2 for body centered cubic structure (bcc) z = 4 for face centered cubic structure (fcc) […]

Calculating Avogadro’s Number In a Solid Crystal Ionic Compound density = Z x M / x Where Z – is the number of atoms per unit cell, Value for z z = 1 for simple cubic cell (scc) z = 2 for body centered cubic structure (bcc) z = 4 for face centered cubic structure […]

Calculating The Density Of a Crystal Lattice density = Z x M / x Where Z – is the number of atoms per unit cell, Value for z z = 1 for simple cubic cell (scc) z = 2 for body centered cubic structure (bcc) z = 4 for face centered cubic structure (fcc) M […]